Conventional welding helmets or hoods are generally formed with a molded plastic or fiber glass face cover with a dark glass viewing port in the front. The welding helmet is open at the top and the back and provides no protection from the arc welding rays, sparks, slag and spatter from other welders who may be operating above or behind. Arc welding rays or even sunlight can enter the helmet from behind and reflect off the dark glass of the viewing port into the eyes of the welding operator. A recurring problem with the standard helmets is that the sparks, slag and spatter from a welding operation can also enter the helmet from behind or fall directly on the back of the head, neck or collar of the welder.
A variety of head enclosing hoods and shields have been devised for protecting workmen under hazardous conditions. The Cockrill et al. U.S. Pat. No. 2,354,502, the Summers U.S. Pat. No. 2,688,962, the Fahey et al. U.S. Pat. No. 2,882,894, and the Harris U.S. Pat. No. 4,172,294 are representative of such head shields, helmets and hoods which effectively fully enclose the head of a workman. Another example of a helmet or hood enclosure is the WHITECAP (TM) Protective Unit for industrial and agricultural employees who work in hazardous or uncomfortable areas manufactured by Personal Environment Systems.
A disadvantage of such protective enclosures is that air circulation around the worker's face and head is cut off and a separate air hose and air supply must be provided for the hood or helmet. Sound transmission is also cut off and the worker cannot respond to environmental sounds creating new safety hazards. Furthermore, the increased weight and material of the enclosing hoods and helmets impede worker mobility increase working temperatures inside the helmet and require substantially greater expense. Finally, the full helmet or hood enclosure must be worn under all circumstances whether required or not.